Wellbore tubular and method

ABSTRACT

A wellbore tubular comprising: a base pipe including a wall; a port through the wall providing access between an inner diameter of the base pipe and an outer surface of the base pipe; a nozzle in the port, the nozzle including an orifice including a bend therein; and a diffuser positioned on the outer surface aligned with the orifice.

FIELD

The invention relates to wellbore structures and, in particular, nozzles and tubulars for wellbore fluid control.

BACKGROUND

Various wellbore nozzles and tubulars are known and serve various purposes. Tubulars are employed to both inject fluids into and conduct fluids from a wellbore. In some cases, nozzles are employed to control the flow and pressure characteristics of the fluid moving through the wellbore.

Wellbore tubulars with nozzles have failed in some challenging wellbore conditions, such as in steam or acid injection operations. Improved nozzled tubulars are of interest.

SUMMARY

In accordance with another broad aspect, there is a wellbore tubular comprising: a base pipe including a wall; a port through the wall providing access between an inner diameter of the base pipe and an outer surface of the base pipe; a nozzle in the port, the nozzle including an orifice; and a diffuser tube on the outer surface to receive fluid exiting the orifice, the diffuser tube including an inlet port opening to an inner diameter within a tubular wall of the diffuser tube, a fluid diffusing wall at a bend within the diffuser tube and a plurality of outlet ports from the diffusing tube.

In accordance with another broad aspect, there is a method for handling fluid in a wellbore comprising: forcing fluid flows through a nozzle orifice which extends from an inner diameter of a tubular to an outer surface of the tubular; and directing the fluid flowing from the nozzle orifice along the outer surface and into a diffuser tube to diffuse energy of the fluid flowing from the nozzle orifice before the fluid exits the tubular.

It is to be understood that other aspects of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein various embodiments of the invention are shown and described by way of illustration. As will be realized, the invention is capable for other and different embodiments and its several details are capable of modification in various other respects, all without departing from the spirit and scope of the present invention. Accordingly the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

Drawings are included for the purpose of illustrating certain aspects of the invention. Such drawings and the description thereof are intended to facilitate understanding and should not be considered limiting of the invention. Drawings are included, in which:

FIG. 1 is a perspective view of a wellbore tubular;

FIG. 2 is a section along line I-I of FIG. 1;

FIG. 3 is a section through line II-II of FIG. 2;

FIG. 4 is an enlarged section through a nozzle installed in the wall of a tubular;

FIG. 5 is an exploded perspective view of the components of a nozzle to be installed in the wall of a tubular;

FIG. 6 is a perspective view of a nozzle seat;

FIG. 7 is an enlarged sectional view of a nozzle;

FIG. 8 is an enlarged section through a nozzle installed in the wall of a tubular;

FIG. 9 is an axial sectional view through a tubular with a diffuser therein;

FIG. 10 is a section along of FIG. 9;

FIG. 11 is a section along IV-IV of FIG. 10;

FIG. 12 is sectional view of another tubular, the sectional view being similar to that of FIG. 10, but passing through the nozzle;

FIG. 13 is a perspective view of the diffuser and nozzle arrangement of the tubular of FIG. 12 with the shield removed; and

FIG. 14 is a section along V-V of FIG. 13.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

The detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor. The detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.

Referring to FIGS. 1 to 3, a wellbore tubular 10 is shown. The wellbore tubular is for conveying fluid into or out of a well and for permitting fluid to pass between its inner diameter and its outer surface. The tubular has a durable construction and may even accommodate the significant rigors presented by handling steam flows. The wellbore tubular may be formed using various constructions. For example, the ends 10 a of the wellbore tubular may be formed for connection to adjacent wellbore tubulars. As will be appreciated, while the tubular's ends are shown as blanks, they may be formed in various ways for connection end to end with other tubulars to form a string of interconnected tubulars, such as, for example, by formation at one or both ends as threaded pins, threaded boxes or other types of connections.

Wellbore tubular 10 includes a base pipe 12 with one or more ports 14 through the base pipe wall. Fluids may pass through ports 14 between the base pipe's inner diameter ID defined by inner surface 12 a and its outer surface 12 b. Depending on the mode of operation intended for the wellbore tubular, fluid flow can be inwardly through the ports toward inner diameter ID or outwardly through the ports from inner diameter ID to the outer surface 12 b.

The inner diameter generally extends from end to end of the tubular such that the tubular can act to convey fluids from end to end therethrough and be used to form a length of a longer fluid conduit through a plurality of connected tubulars.

The tubular may include a shield 16 mounted to base pipe 12. The shield may be positioned to overlap the ports. Shield 16 may be spaced from outer surface 12 b such that an annular space 18 is provided between the shield and outer surface 12 b.

There are openings from space 18 to the exterior of the tubular, which is the outer surface 12 b exposed beyond the shield. For example, there may be openings 18 a through the shield or at the end edges 16 a of shield 16 where fluid can flow into or out of space 18. In the illustrated embodiment of FIG. 2, shield 16 is spaced at at least some edges 16 a from outer surface 12 b such that there are openings 18 a through which space 18 can be accessed at those edges. In some embodiments, as shown, the shield may be positioned to encircle base pipe 12 at the ports 14 and, therefore, may be shaped as a sleeve, as shown with space 18 formed as an annulus and with annular access openings 18 a at both ends of the sleeve.

The openings may take other forms in other embodiments, depending on the form of the base tubular, sleeve, and mode of operation. For example, in one embodiment, the 118 a openings may be formed in whole or in part by grooves 119 in the outer surface 112 b of the base pipe (FIG. 8).

Shield 16 may serve a number of purposes including, for example, protecting the ports from abrasion and diverting flow for fluid velocity control. For example, shield 16 diverts flow between the exterior of the tubular and ports 14, such that it must pass along outer surface 12 b of base pipe. Flow, therefore, cannot pass directly radially between the exterior of the tubular and inner diameter ID. In particular, because shield 16 overlaps the ports, ports 14 open into space 18, flow between exterior of the tubular and the inner diameter changes direction at least once: at the intersection of port 14 and space 18. While flow through the ports 14 is radial relative to the long axis xb of the tubular, flow between the ports and the exterior of the tool is through space 18 and that flow is substantially orthogonal relative to the radial flow through ports 14.

Each port 14 has a nozzle assembly 20 installed therein. The nozzle assembly permits flow control through the port in which it is installed. With reference also to FIG. 4, nozzle assembly 20 includes at least a nozzle 22 and may include an installation fitting 24.

Nozzle 22 includes an orifice 26 extending through the nozzle body through which fluid passes through the nozzle and therefore through the port. In particular, a nozzle 22 is installed in each port such that flow through the port is controlled by the shape and the configuration of orifice 26.

Nozzle 22 is formed of a material that can withstand the erosive rigors experienced down hole such as via abrasive flows, high velocity flows, corrosive flows with acid and/or steam passing through orifice 26. Nozzle 22 may, for example, be formed of a material different, for example, harder than the material forming base pipe 12. The base pipe is, for example, usually formed of steel such as carbon steel and nozzle 22 may be formed of a material harder than the carbon steel of base pipe 12. In some embodiments, for example, nozzle 22 may be formed of tungsten carbide, stainless, hardened steel, filled materials, etc.

Orifice 26 may be shaped to allow non-linear flow through nozzle 22. In particular, orifice 26 defines a path through the nozzle, through which fluid flows, and the path from its inlet end to its outlet end is non-linear, including at least one bend or elbow that causes at least one change in direction of the fluid flowing through the orifice. This bend may affect fluid flows in a number of ways to redirect the flow to a more favorable direction, to cause impingement of the fluid against a nozzle surface or another flow to diffuse energy from the flow, to mitigate erosive damage to certain surfaces and/or to create an extra back pressure to slow or otherwise control flows of certain fluids autonomously through the nozzle. For example, the geometry of the nozzle orifice 26 can be selected to choke selectively gas, water, steam or oil.

For example with reference also to FIG. 7, orifice 26 may include a diverting bend at y that diverts flow through the nozzle from a first direction to a second direction which is offset, out of line from the first direction. With reference to the direction of flow depicted through the nozzle of FIG. 7, the first direction is shown by arrow Fa and the second direction is shown by arrow Fb. In one embodiment, the second direction is substantially orthogonal to the first direction.

Nozzle 22 is positioned in a port and will have one end open to the inner diameter ID of the tubular and the other end open to the outer surface 12 b. Generally, the nozzle is installed so that a base end 22 a is installed adjacent and open to inner surface 12 a and an opposite end 22 b is installed adjacent and open to outer surface 12 b. Orifice 26 may be formed, therefore, to avoid straight through flow between base end 22 a and opposite end 22 b. Orifice 26, for example, may include a portion defining a main aperture 26 a and a portion defining a lateral aperture 26 b. Main aperture 26 a extends from an opening 26 a′ at a base end 22 a of nozzle 22 to an end wall 26 a″ at an opposite end 22 b of the nozzle. Lateral aperture 26 b extends from the main aperture and connects main aperture 26 a to another opening 26 b′ adjacent opposite end 22 b. Lateral aperture 26 b extends at an angle from the long axis of main aperture 26 a. The angular intersection of the axis of lateral aperture relative to the main aperture may be substantially orthogonal (+/−45°) and in one embodiment, for example, the apertures 26 a, 26 b intersect at y at substantially 90°.

The nozzle may be substantially cylindrical with ends 22 a, 22 b and substantially cylindrical side walls extending between the ends. In such an embodiment, the main aperture portion opens at an end and the pair of lateral aperture portions opens on the cylindrical side walls.

End wall 26 a″, which can be flat (planar) or domed (concave), prevents straight through flow through the nozzle and acts to divert flow from the first direction in the main aperture to the lateral direction through lateral aperture 26 b. Impingement of fluid flows against wall 26 a″ dissipates energy from the flow and concentrates erosive energy against wall 26 a″ rather than surfaces beyond the nozzle. Orifice 26 is formed through the material of the nozzle and, thus, walls 26 a″ and the other walls defining orifice 26 are of erosion-resistant material. Thus, the diverting bend and in particular end wall 26 a″, can reliably accommodate the passage therethrough of erosive flows including that of steam. This foregoing description focuses on flow in only one direction through apertures 26 a, 26 b, but it is to be understood that flow can be from opening 26 b′ to opening 26 a′ (i.e. with the flow moving in the opposite directions of arrows Fa and Fb), if desired. See for example, FIG. 8 wherein flow arrows F through nozzle 122 pass in the opposite direction: from outer lateral aperture portions 126 b to main aperture portion 126 a of orifice 126.

Orifice 26 may be further configured to control the flow characteristics of fluid passing therethrough. In one embodiment, apertures 26 a, 26 b may be sized to limit the volume of fluid capable of passing therethrough. For example, apertures 26 b may be smaller diameter openings, sized to allow less flow, than aperture 26 a. For example, the total cross sectional area of apertures 26 b may be less than the total cross sectional area of aperture 26 a, such that a back pressure is created when flow is in the direction of arrows Fa, Fb. Stated another way, the pressure drop is mainly across 26 b. The primary flow control through the nozzle is at lateral aperture 26 b, more so than 26 a.

Alternately or in addition, apertures 26 a, 26 b may be shaped to impart desired flow rate and/or pressure on the fluid passing therethrough. For example, lateral aperture 26 b, as shown, has internal shape with a jetting constriction to impart a jet effect, which generally includes a fluid acceleration and pressure change (i.e. drop), in the fluid passing therethrough. The shape of apertures 26 a may change depending on whether the flow is intended to be with arrows Fb or against them or a bidirectional jetting shape may be employed with a symmetrical constriction similar to an hour glass.

In addition or alternately, there may be more than one main and/or lateral aperture. For example, as shown, orifice 26 may take the form of a T-shaped conduit with at least two lateral apertures 26 b extending from the main aperture. However, while two lateral apertures 26 b are shown, there may be only one or more than two such apertures. Generally, there will be an even number of lateral apertures with pairs substantially diametrically opposed across the circumference of the main aperture 26 a. The diametric positioning, with one lateral aperture 26 b opening into main aperture 26 a at a position substantially opposite another lateral aperture 26 b (as shown in FIG. 7), allows fluid impingement when flow is inwardly from apertures 26 b to aperture 26 a. This impingement may create a desired back pressure on the flow through nozzle.

Nozzle 22 conveys fluid between openings 26 a′ and 26 b′ across the wall of the base pipe. One opening is exposed in the inner diameter of the base pipe and the other opening is exposed on outer surface 12 b. If shield 16 is employed, fluid when exiting from nozzle 22, enters annulus 18. The position of orifice 26 b′ of lateral aperture 26 b causes some fluid movement parallel to outer surface 12 b, rather than straight radially out from port 14.

Nozzle 22 may be installed in any of various ways in its port 14. If desired, nozzle assembly 20 may include installation fitting 24 to hold nozzle 22 in its port 14. For example, if the material of nozzle 22 prevents reliable engagement to base pipe or is formed of a material different than the material of the base pipe, a fitting 24 may be employed to ensure a good fit of the nozzle in its port and may, for example, reduce the risk of nozzle 22 falling out of the port.

Installation fitting 24 may be formed to fit between the nozzle and the port. For example, the installation fitting may include a portion for being engaged in the port and a portion for securing nozzle. The portion for being engaged in the port may vary depending on the form and the shape of the port and the desired mode of installation in port 14. In the illustrated embodiment, for example, installation fitting 24 includes a threaded portion 28 as that portion engageable in the port. The port may also include threads 30 into which fitting 24 may be threaded.

The portion for securing the nozzle may also vary, for example, depending on the form and shape of nozzle 22 and the desired mode of installation of nozzle 22. For example, in one embodiment, nozzle 22 can be held rigidly by the fitting and in another embodiment, nozzle 22 may be installed to have some degree of movement relative to the fitting, while being held against becoming entirely free of the fitting. Thus, as an example, fitting 24 in the illustrated example includes a passage 32 into which nozzle 22 fits. Passage 32 passes fully through the fitting such that it is open at both ends of the fitting and, in other words, the fitting is formed as a ring. When nozzle 22 is installed in passage 32, opening 26 a′ is exposed at one end of the passage and opening 26 b′ is exposed at the other end of the passage.

In this embodiment, nozzle 22 is secured rigidly into passage 32. For example, nozzle 22 may be press fit and possibly mechanically shrunk fit, into passage 32. In one embodiment, fitting 24 may be heated to cause thermal expansion thereof that enlarges the diameter across passage 32, nozzle 22 may be fit therein and fitting 24 cooled to contract about the nozzle and, thereby, firmly engage it. In such an embodiment, fitting 24 may include features to modify the hoop stresses about the ring to best accommodate heating expansion for press fitting. For example, passage 32 and nozzle 22 may have a tapering diameter from end to end to facilitate press fitting these parts together. For example, nozzle 22 may have a tapering outer diameter from one end to the other and passage 32 may have a tapering inner diameter from one end to the other end. The nozzle 22 may then be inserted and forced into passage 32 with the narrow end of the nozzle wedged into the narrow end of the passage and the tapering sides of the parts in close contact. In addition or alternately, for modification of hoop strength, passage 32 may include notches 34 in the otherwise substantially circular sectional shape (orthogonal to the center axis x of passage 32).

In some embodiments, the material of nozzle 22 may have thermal expansion properties different than the material of base pipe 12. As such, if nozzle 22 was installed directly into base pipe 12, it may tend to become dislodged or damaged in use such as when in a high temperature (i.e. steam) environment. Generally, the materials most useful for the nozzle may have a low coefficient of thermal expansion, while the materials most useful for the base pipe 12 may have a reasonably high coefficient of thermal expansion and most often a nozzle firmly installed in a port at ambient temperatures may tend to fall out of a base pipe at elevated temperatures. To address issues caused by thermal expansion, installation fitting 24 may be formed of a material having a coefficient of thermal expansion selected to work well with both the nozzle and the base pipe. In one embodiment, installation fitting 24 is formed of a material having a coefficient of thermal expansion between those of the materials of the base pipe and the nozzle. In another embodiment, the coefficient of thermal expansion of fitting 24 is greater than that of base pipe 12. As such, when undergoing thermal stress, fitting 24 will undergo thermal expansion ahead of base pipe 12 and fitting 24 stays firmly engaged in port. In such an embodiment, nozzle 22 and fitting 24 can be connected when the fitting is thermally expanded.

Shield 16, if employed, may overlap the nozzle assembly to hold nozzle 22 in the port 14. In one embodiment, nozzle 22 is fit in the port such that any movement to fall out of port is radially out towards outer surface 12 b. A controlled installation that tends to allow nozzle 22 to only move outwardly towards the outer surface may be achieved, for example, by tapering of the nozzle and the port/passage in which it is installed to have their wider ends radially outwardly positioned, for example closer to the outer surface of the base pipe. Shield 16 includes a plug 36 in a hole 38 that substantially radially aligns with port 14. Plug 36 is removable to allow opening of hole 38 and access to port 14 and, thereby, installation of nozzle assembly 20 to port 14 through hole 38. After nozzle 22 is installed, plug 36 may be reinstalled in hole 38 to overlie the nozzle. Plug 36 and hole 38, for example, may be threaded to facilitate removal and reinstallation of the plug.

Plug 36 can ensure that nozzle 22 remains in position in port 14 even if nozzle 22 comes loose. For example, plug 36 can be formed to penetrate into hole 38 sufficiently to bear down on end 22 b of the nozzle. If there are tolerances that may prevent reliable fitting of the plug against end 22 b of the nozzle, a flexible spacer may be employed. For example, as shown, there may be a spring 40 between plug 36 and nozzle 22.

Nozzle assembly 20, in this embodiment including nozzle 22 and fitting 24 in port 14, allows fluid to move between inner diameter ID and outer surface 12 b through orifice 26. The lateral orifice 26 b directs fluid flows that are adjacent opening 26 b′ to pass substantially parallel to outer surface 12 b through annulus 18. To facilitate flows through the annulus with minimal erosive damage to shield 16, aperture 26 b may be positioned such that flows therethrough pass somewhat parallel to the long axis xb of base pipe. For example, the nozzle 22 can be installed such that the axis xa of aperture 26 b is within 60° and perhaps within 45° of long axis xb. In the illustrated embodiment, axis xa of aperture 26 b is substantially aligned with long axis xb.

To install a nozzle assembly in such an embodiment, plug 36 can be removed from hole 38, the nozzle assembly including at least nozzle 22 but possibly also fitting 24 can be inserted through hole 38 and installed in port 14 with openings 26 a′ and 26 b′ exposed in inner diameter ID and annulus 18, respectively, and with axis xa of aperture 26 b directed in a selected direction, for example toward the open edges 16 a of shield 16. Then plug 36 can be installed in hole 38 over nozzle 22. If there is a spacer, such as spring 40, it is positioned between nozzle 22 and plug 36. In an embodiment where the nozzle assembly includes fitting 24 and nozzle 22, these parts can be installed separately or may be connected ahead of installation.

Tubulars according to the present invention can take other forms as well. In one embodiment, as shown in FIG. 8, tubular 110 includes a screening apparatus 150. Tubular 110 is primarily useful for handling inflows, since screening apparatus 150 removes oversize particles from the flows to opening 118 a. Grooves 119 in outer surface 112 b extend under apparatus 150, through openings 118 a under an edge of the shield and into space 118 between outer surface 112 b and shield 116. Space 118 opens to nozzle. It is noted that tubular 110 illustrates a nozzle 122 without an additional installation fitting and, instead, nozzle 122 is secured directly into the material of base pipe.

During use of the tubular, fluid may pass through nozzle orifice 26 between inner diameter ID and outer surface 12 b. Nozzle 22 diverts flow such that it passes in a non-linear fashion between inner diameter ID and outer surface 12 b. Orifice 26 causes fluid flows to change direction as they pass through the nozzle including both: (i) substantially radially relative to the long axis xb of the base pipe and (ii) substantially parallel to the outer surface, which is possibly somewhat parallel to the long axis of the base pipe. This may direct flows through space 18 between outer surface 12 b and shield 16 spaced from the outer surface. The fluid may flow through space 18, along outer surface 12 b through an opening 18 a, 118 a to the annulus about the tubular.

Flows outwardly tend not to cause formation damage, as the fluid jetting through the nozzle is diverted from a radially outward direction (through aperture 26 a) to a lateral direction through aperture 26 b and along the outer surface of the base pipe, which is parallel to the wellbore wall. As such, the force of the fluid passing from the tubular is dissipated at end wall 26 a″ of the orifice, where the flow path diverts laterally.

In use, nozzle 22 may control fluid flows by accommodating and avoiding erosion through ports and controlling velocity and pressure characteristics of the flow.

For example, a method for accepting inflow of steam or produced fluids in a paired, heavy oil (such as oil sand), gravity drainage well may employ a tubular such as is depicted in FIGS. 1 to 3 or FIG. 7. In paired well steam production, it is desirable that introduced steam create a steam chamber in the formation that heats the heavy oil and mobilizes it as produced fluids. The produced fluids are intended to flow into a producing well. Sometimes steam from an adjacent well may break through and seek to enter the producing well. Using a tubular, as described, steam may be restricted from passing into the tubular due to the form of the nozzle and the configuration of the nozzle in the tubular. In particular, the limited entry size of the apertures first limits the volume of produced fluids that can pass into the tubular. Also, the impingement of flows from the diametrically opposed apertures 26 b tends to resist flows through the orifice 26 and creates a back pressure that limits flows through the nozzle. Also, the diverted flow path from aperture 26 b to aperture 26 a dissipates fluid force so that the tubular tends not to problematically erode. As such, a steam chamber may form outwardly of the tubular, even if a break through occurs from the steam injection well to the producing well.

During use, while forces may tend to act to dislodge nozzle from its position, the method may include holding the nozzle in place against the forces tending to move the nozzle into an inactive position. For example, the method may include holding the nozzle down into the port, for example, by a shield thereover. Alternately, or in addition, the method may include holding the nozzle against dislodgement by differences in thermal expansion, for example, by use of a fitting. A fitting may act between the nozzle and the base pipe to hold the nozzle in place. For example, the fitting may prevent the nozzle from passing into the inner diameter due to a taper in the parts and the nozzle may have a thermal expansion that holds the nozzle in place.

While the embodiment is described wherein nozzle 22 is rigidly installed in fitting 24, the nozzle in some embodiments can be slidably mounted in the fitting. For example, nozzle can slide into and out of the fitting depending on the pressures against openings 26 a′ and 26 b′. As such, nozzle 22 can operate as a form of valve.

A nozzle, as described hereinbefore, may have an orifice shaped to restrict flow in one direction, but such an orifice may not restrict flow as much in the opposite direction. For example, with reference to FIGS. 9 to 13, a nozzle 222 may be installed in a tubular 212 intended to handle produced fluid flow, which is flow inwardly from the base pipe's outer surface 212 b through the orifice of the nozzle. Specifically, with reference back to FIG. 8, inward, produced fluid flow may be through a lateral aperture 126 b of the orifice and then into a main aperture 126 a of the orifice, before entering the inner diameter ID of the tubular. In such an embodiment, each orifice lateral aperture 126 b has a smaller diameter inner end (the end closer to main aperture 126 a) and a larger diameter outer end (the end closer to space 118) and a flaring diameter from the inner end to the outer end. This orifice shape creates back pressure on the fluid passing therethrough in the direction of arrows F.

With such a tubular, flow in the opposite direction, outwardly from the inner diameter, ID through nozzle 122 to outer surface 112 b may not be slowed by the orifice and may, in fact, be accelerated such that the fluid passing from nozzle 122, out through lateral aperture 126 b along outer surface 112 b may have a high velocity and may be damaging to structures in the fluid path, especially if the fluid is steam or acid.

For example if it is desired to use tubular 110, that is intended to control and slow inflow of produced fluids into the tubular inner diameter, instead to pump fluids through from the tubular into the formation (in a direction opposite arrows F), the fluids passing from nozzle 122 may damage structures including parts of the tubular such as shield 116, base pipe outer surface 112 b, screening materials 150, or the formation. Fluids, such as water, gas, steam or acid, passing from the nozzle orifice 126 b may cause erosion-corrosion.

A tubular 210 that provides both controlled, low stress inflow and controlled, low stress outflow through a nozzle 222 may include an outflow diffuser 260 positioned to accept flow from the nozzle. The outflow diffuser 260 accepts flow and dissipates some of the energy therefrom before releasing the flow to exit and flow away from the tubular. The diffuser includes a wall positioned out of alignment, for example substantially orthogonally, to the axis xa (see FIG. 7) of the orifice's lateral apertures 226 b.

The diffuser may be installed on outer surface 212 b of the tubular wall to receive impingement from an outward flow from nozzle 222, which will be through the orifice's lateral apertures 226 b. There may be a diffuser for each lateral aperture of the nozzle. The diffuser is positioned adjacent the nozzle and generally in a space such as an exterior fluid chamber 218 such as one defined between a shield 216 and outer surface 212 b. The exterior fluid chamber has an opening 218 a to the exterior of the tool through which fluid enters or exits the chamber. When fluid is passing outwardly through nozzle 222, it follows an exit path from nozzle to opening 218 a where the fluid passes out from under the shield 216 to the exterior of the shield. Opening is part of the exit path for the fluid. The opening 218 a may open directly to the exterior of the tool. Alternately, a filtering material 250 may be disposed across opening 218 a to filter fluid passing through opening 218 a.

In one embodiment, the diffuser is a tube positioned and configured to accept fluids exiting the nozzle at lateral apertures 226 b and redirect and slow the fluids before releasing them to continue along the exit path and flow from the tubular. The diffuser tube has a tubular construction with a tubular wall defining there within an inner diameter that provides a conduit for fluids to flow between an inlet port 262 to the tube and a plurality of outlet ports 264 from the tube. The inlet port may have a diameter larger than the diameter of each individual outlet port 264. The diffuser tube may be formed with an elbow 266 along its conduit length such that flow passing therethrough is redirected and does not pass straight through. The elbow creates the wall positioned out of alignment, for example substantially orthogonally, to the axis xa (see FIG. 7) of the orifice's lateral aperture 226 b. The tube in one embodiment is L or T-shaped with an inlet portion 270, which is a length of the tube having the inlet port 262 at one end thereof and elbow 266 at the other end and one or more, such as for example two, arm portions 272 extending from the inlet portion at the elbow. Outlet ports 264 are positioned in the arm portions 272, but are spaced from elbow 266. The outlet ports may be holes through the tubular wall forming the arm portions and/or may be holes at the end of the arm portions. The inner diameter of the inlet portion opens at the elbow into the inner diameters of the arm portions. Thus, fluid passing through the conduit of the tube enters through the inlet port and impinges against an end wall 266 a at the bend of elbow 266. The end wall 266 a causes the fluid to change direction and flow down arm portions 272.

In one embodiment, the diffuser tube is T-shaped with inlet portion 270 connected to two arm portions at a T-shaped elbow. The diffuser tube may be substantially symmetrical about the inlet portion.

The diffuser is positioned on the outer surface of the wall of the tubular 212 adjacent the orifice of nozzle 222 to receive the fluid passing from lateral aperture 226 b. In one embodiment, inlet port 262 is positioned substantially aligned with lateral aperture 226 b. For example, inlet port 262 may be positioned such that its center point is axially aligned with axis xa of the nozzle's lateral aperture 226 b. Inlet port 262 may be flared and may taper across its inner diameter with depth into the inlet port. This flare causes the inlet port opening of the diffuser to be conically formed and creates a wider entry site to the diffuser. This ensures that most if not all of the fluid passing from lateral aperture 226 b passes into the diffuser conduit 260.

The arm portions 272 extend from inlet portion 270. Since the diffuser is positioned on the wall of tubular 212, arm portions 272 may be curved to substantially follow the circumferential curvature of the tubular's wall. In one embodiment, the long axis of inlet portion 270 extends substantially in alignment with long axis xb of the tubular body 212 and arms 272 are attached to the inlet portion and are curved to extend around the circumferential curvature orthogonal to the long axis xb of the tubular body.

As noted above, outlet ports 264 are positioned in the arm portions 272. Ports 264 may be positioned in the end of the arm portions 272 and/or may be positioned spaced apart along the length of each arm portion. In one embodiment, the ports 264 are positioned to direct the fluid passing therethrough into a particular area of the tubular. In one embodiment, for example, ports 264 are positioned in arm portions 272 such that fluid exiting therefrom cannot flow directly along a straight line to the exit opening 218 a on the tubular. For example, ports 264 can be positioned in arm portions 272 such that fluid passing from the ports must change direction to reach the exit opening 218 a. The ports, for example, may be oriented to face towards a blocking structure such as towards the outer surface, the shield or another diffuser. Alternately, the ports may be positioned to expel fluid into counter or cross flowing fluid path or along a path not directly parallel to the exit path leading to exit opening 218 a. For example, if there are two diffuser tubes in the tubular, they may be positioned such that their outlet ports 264 face each other. In the illustrated embodiment, for example, ports 264 are positioned in arm portions 272 on a side that faces away from the exit path of the fluid. The ports open towards another diffuser and, in particular, toward ports 264 on that other diffuser. Additionally, at least some ports are angled up toward shield 216 and/or angled down toward surface 212 b, which are the walls that define the upper and lower limits, respectively, of the exterior fluid chamber 218. As such, ports 264 in the illustrated embodiment, are positioned to expel fluid away from opening 218 a into a counter flowing fluid path generated by fluid expelled from the opposite diffuser and upwardly or downwardly at an angle to impinge against the upper or lower limits of the chamber in which they are installed.

While, the diffuser may be installed in the tubular to receive an outward flow from nozzle 222, a bypass opening may be provided to permit produced fluid to bypass the diffuser and enter the nozzle without first passing through the diffuser. The fluid may, therefore, enter the nozzle directly to flow inwardly into the inner diameter without flowing through the diffuser. In the illustrated embodiment, diffuser conduit 260 is spaced from the nozzle such that there is an open space 280 between the nozzle and the inlet portion 270 of the diffuser. Produced fluid may flow through opening 218 a, into open space 280 and then enter nozzle directly to thereby flow inwardly into the inner diameter, while bypassing at least the arm portions and elbow, and possibly the entirety, of the diffuser. The bypass opening may take other forms such as large holes through the inlet portion, if the diffuser if attached directly adjacent the nozzle.

In addition, if desired, the diffuser may be mounted in chamber 218 with gaps 282 between the upper and/or lower surfaces of the arm portions 272 and the shield 216 and/or surface 212 b such that produced fluid can pass above and below the diffuser to enter the nozzle's orifice without flowing through the diffuser.

In spite of these gaps 282 and open space 280, diffuser 260 is installed to be held firmly in its position adjacent the nozzle. In one embodiment, there is a mounting block 286 that secures the diffuser in position between shield 216 and base pipe 212. In FIG. 11, mounting block 286 is sandwiched and secured between the shield and the base pipe and in the tubular of FIG. 12, mounting block 286 is installed in a recess 288 in the shield. In any event, the mode of installation such as the use of mounting block 286 maintains gaps 282 and spacing at open space 280, to secure the diffuser against being pushed away from the nozzle by the force of the fluid flow.

Diffuser 260, especially at inlet port 262, outlet ports 264 and elbow 266, must withstand a lot of erosive fluid force. As such, diffuser 260 may be constructed of a durable material similar to those used for the nozzle. While the use of such material may be costly, the amount of this material required for nozzle 222 and diffuser 260, may be small compared to the overall material requirements of the tubular. These parts, the nozzle and the diffuser can be installed in a tubular formed of standard construction materials.

The spacing between the diffuser and the nozzle may determine how much of the nozzle's flow is treated via the diffuser and the force at which the fluid enters the inlet portion. This spacing may be varied as desired in the construction of the tubular.

The tubulars of FIGS. 10 and 13 differ in a few respects including the shape and mode of installation of the mounting portion 286. These two embodiments also show two different installations for nozzle 222, wherein FIG. 10 shows the nozzle formed as an integral component of the base pipe and FIG. 13 shows the nozzle as an insert installed through a capped port, such as is described in FIG. 3.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to those embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the full scope consistent with the claims, wherein reference to an element in the singular, such as by use of the article “a” or “an” is not intended to mean “one and only one” unless specifically so stated, but rather “one or more”. All structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. For US patent properties, it is noted that no claim element is to be construed under the provisions of 35 USC 112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or “step for”. 

We claim:
 1. A wellbore tubular comprising: a base pipe including a wall; a port through the wall providing access between an inner diameter of the base pipe and an outer surface of the base pipe; a nozzle in the port, the nozzle including an orifice; and a diffuser tube on the outer surface to receive fluid exiting the orifice, the diffuser tube including an inlet port opening to an inner diameter within a tubular wall of the diffuser tube, a fluid diffusing wall at a bend within the diffuser tube and a plurality of outlet ports from the diffusing tube.
 2. The wellbore tubular of claim 1 wherein the inlet port is spaced from the nozzle orifice.
 3. The wellbore tubular of claim 1 further comprising a shield connected over the outer surface of the base pipe and forming a fluid chamber between the shield and the outer surface and wherein the orifice opens into the fluid chamber and the diffuser tube is positioned in the fluid chamber.
 4. The wellbore tubular of claim 3 wherein the inlet port and the plurality of outlet ports are positioned in the fluid chamber.
 5. The wellbore tubular of claim 3 wherein the shield is an annular sleeve and a gap between an end of the annular sleeve and the outer surface forms an exit opening from the fluid chamber an exterior of the wellbore tubular, and the outlet ports are positioned on a side of the diffuser tube facing away from the exit opening.
 6. The wellbore tubular of claim 1 wherein the plurality of outlet ports open towards an outlet port on a second diffuser such that the plurality of outlet ports are configured to expel fluid into a counter or cross flowing fluid path exiting from the second diffuser.
 7. The wellbore tubular of claim 3 wherein at least some of the plurality of outlet ports are angled up toward the shield.
 8. The wellbore tubular of claim 1 wherein the orifice includes a main aperture extending radially out from the inner diameter and a lateral aperture extending at an angle from the main aperture bend that changes the direction of fluid passing through the orifice and a long axis through the lateral aperture is substantially parallel to the outer surface and wherein the lateral aperture has an inner end closest to the main aperture and an outer end opposite the inner end and the lateral aperture has a larger diameter at the outer end than the inner end.
 9. The wellbore tubular of claim 1 wherein the nozzle includes a second lateral aperture and a second diffuser tube on the outer surface to receive fluid exiting the second lateral aperture.
 10. The wellbore tubular of claim 1 wherein the inlet port has a diameter larger than an individual diameter of each individual outlet port.
 11. The wellbore tubular of claim 1 wherein the diffuser tube includes an elbow between the inlet port and the plurality of outlet ports.
 12. The wellbore tubular of claim 11 wherein the elbow creates a wall in the inner diameter, the wall being substantially orthogonally oriented relative to an axis of the orifice as it exits the nozzle.
 13. The wellbore tubular of claim 11 wherein the diffuser tube includes an inlet portion with the inlet port at one end and the elbow at the other end and a first arm portion extending from the elbow and a second arm portion extending from the elbow, the plurality of outlet ports being on the first and second arm portions and the diffuser tube is T-shaped in plan view.
 14. The wellbore tubular of claim 13 wherein the inlet portion is substantially aligned with a long axis through the base pipe and the first and second arm portions are curved to substantially follow a circumferential curvature of the base pipe outer surface.
 15. The wellbore tubular of claim 1 wherein the inlet port includes a conical, flaring extension.
 16. The wellbore tubular of claim 1 further comprising a bypass opening between the nozzle and the inlet port configured to permit fluid to bypass the diffuser tube and enter the nozzle without first passing through the diffuser tube.
 17. The wellbore tubular of claim 1 wherein the diffuser tube is constructed of a material more durable to erosion than a material from which the base pipe is constructed.
 18. A method for handling fluid in a wellbore comprising: forcing fluid flows through a nozzle orifice which extends from an inner diameter of a tubular to an outer surface of the tubular; and directing the fluid flowing from the nozzle orifice along the outer surface and into a diffuser tube to diffuse energy of the fluid flowing from the nozzle orifice before the fluid exits the tubular.
 19. The method of claim 18 further comprising: handling produced fluid flows by permitting produced fluid to enter the nozzle orifice from adjacent the outer surface and flowing towards the inner diameter, the nozzle orifice configured to generate a back pressure on the produced fluid flows such that the pressure is higher at the outer surface than in the inner diameter.
 20. The method of claim 19 wherein handling produced fluid flows permits the produced fluid flows to flow into the nozzle orifice while bypassing the diffuser tube.
 21. The method of claim 18 wherein directing the fluid flowing from the nozzle orifice at the outer surface into a diffuser tube includes introducing the fluid through an inlet port into an inner diameter of the diffuser tube, impinging the fluid against a wall in the inner diameter to change direction of the flow and permitting flow out of the diffuser tube through an outlet port.
 22. The method of claim 21 wherein permitting flow out of the diffuser tube directs the flow into a flow path of fluids exiting another diffuser tube.
 23. The method of claim 18 wherein the tubular includes an exit opening from the tubular and wherein the fluid exits the tubular through the exit opening.
 24. The method of claim 23 wherein after passing from the diffuser tube, changing a flow direction of the fluid before the fluid passes through the exit opening.
 25. The method of claim 23 wherein directing the fluid flows includes impinging the fluid flows exiting from the diffuser tube against a redirecting surface before passing through the exit opening. 